SIP

For most of my career, getting a high-quality audio circuit to or from a remote location meant either booking an ISDN line or arranging a satellite or fibre contribution. ISDN was reliable, well-understood, and nearly universal in broadcast. It was also expensive, inflexible, and is now being switched off across much of the world. The replacement, in most cases, is SIP over IP. And while IP contribution codecs have been around for a long time, SIP as a standardised signalling layer has made a real difference to interoperability - particularly as broadcast facilities want to bring commentary and coordination circuits in from the public internet without needing to manage dedicated infrastructure at the remote end. ...